1 /* $NetBSD: getdtablesize.c,v 1.1.1.1 2011/04/13 18:15:41 elric Exp $ */
2
3 /*
4 * Copyright (c) 1995-2001 Kungliga Tekniska Högskolan
5 * (Royal Institute of Technology, Stockholm, Sweden).
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 *
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * 3. Neither the name of the Institute nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36 #include <config.h>
37
38 #include <krb5/roken.h>
39
40 #ifdef HAVE_SYS_TYPES_H
41 #include <sys/types.h>
42 #endif
43 #ifdef TIME_WITH_SYS_TIME
44 #include <sys/time.h>
45 #include <time.h>
46 #elif defined(HAVE_SYS_TIME_H)
47 #include <sys/time.h>
48 #else
49 #include <time.h>
50 #endif
51 #ifdef HAVE_SYS_PARAM_H
52 #include <sys/param.h>
53 #endif
54 #ifdef HAVE_UNISTD_H
55 #include <unistd.h>
56 #endif
57
58 #ifdef HAVE_SYS_RESOURCE_H
59 #include <sys/resource.h>
60 #endif
61
62 #ifdef HAVE_SYS_SYSCTL_H
63 #include <sys/sysctl.h>
64 #endif
65
66 ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
getdtablesize(void)67 getdtablesize(void)
68 {
69 int files = -1;
70 #if defined(HAVE_SYSCONF) && defined(_SC_OPEN_MAX)
71 files = sysconf(_SC_OPEN_MAX);
72 #else /* !defined(HAVE_SYSCONF) */
73 #if defined(HAVE_GETRLIMIT) && defined(RLIMIT_NOFILE)
74 struct rlimit res;
75 if (getrlimit(RLIMIT_NOFILE, &res) == 0)
76 files = res.rlim_cur;
77 #else /* !definded(HAVE_GETRLIMIT) */
78 #if defined(HAVE_SYSCTL) && defined(CTL_KERN) && defined(KERN_MAXFILES)
79 int mib[2];
80 size_t len;
81
82 mib[0] = CTL_KERN;
83 mib[1] = KERN_MAXFILES;
84 len = sizeof(files);
85 sysctl(&mib, 2, &files, sizeof(files), NULL, 0);
86 #endif /* defined(HAVE_SYSCTL) */
87 #endif /* !definded(HAVE_GETRLIMIT) */
88 #endif /* !defined(HAVE_SYSCONF) */
89
90 #ifdef OPEN_MAX
91 if (files < 0)
92 files = OPEN_MAX;
93 #endif
94
95 #ifdef NOFILE
96 if (files < 0)
97 files = NOFILE;
98 #endif
99
100 return files;
101 }
102